European regulators are investigating Motorola Mobility for allegedly overcharging Microsoft and Apple for use of its industry standard patents in their products, Reuters reported on Tuesday. Both companies filed complaints with the European Commission, which is now conducting the investigation that will look to determine whether Motorola failed to honor its “irrevocable commitments” made to standard-setting organizations. In February, Microsoft had asked antitrust regulators to intervene in its patent dispute with Motorola, claiming the company “has refused to make its patents available at anything remotely close to a reasonable price.” In its complaint, the software giant also named Google, which is in the process of acquiring Motorola. Regulators confirmed that they are investigating Samsung as well in order to determine whether or not the company violated European antitrust laws in its patent disputes with Apple.